In the last issue, I wrote about three New Year's Resolutions to make triathletes fitter and faster in 2008. For the run resolution it was simple: do more tempo runs. Many elite and international coaches will tell you that one big reason that the East Africans are so dominant in distance running is that they do a huge amount of tempo work.

Coach Joe I. Vigil, Ph.D., coach of Athens Olympic marathon medalist Deena Kastor and Meb Keflezighi wrote, "Volume runs, when combined with a regular diet of tempo runs, are the single most important workout for the development of the distance component." Dr. Jack Daniels adds, "Tempo running is one of the most productive types of training that distance runners can do. Training at this pace helps runners avoid overtraining and yields more satisfying workouts and better consistency."

The purpose of tempo runs is to stress lactate clearance, not to overstress it. Done properly, tempo runs will increase anaerobic threshold, the point at which lactic acid starts to accumulate in your muscles. Not so long ago, Vo2max was the physiological measure considered the best indicator of running potential. Vo2max is the maximum amount of oxygen that your body can process to produce energy. The ability to run at the highest possible percentage of a runner's Vo2 for a longer time is the result of one thing--tempo work, and lots of it--over a long time.

All the speed work, weekly mileage and Vo2max workouts won't mean as much as they will with the addition of regular, consistent tempo work. If you read about the Kenyans' training, it revolves around tempo work. Recently, Vo2max has lost its standing as the best predictor of running performance. A new measure, vVo2, has come to the forefront as the best indicator of running performance. vVo2 stands for velocity at Vo2max, or how fast you're running when you reach Vo2max. Thus, it factors in your running economy, in addition to your cardiovascular and muscular capacity.

How Does It Work?

Most runners have trained their bodies with lots of long, slow distance running to deliver oxygen, but they haven't trained their bodies to use it. Tempo running does just that. During tempo runs, lactate and hydrogen ions are released into the muscle. The hydrogen ions make the muscle more acidic. The better trained you become, the higher you push the threshold at which this occurs. This means that your muscles become more efficient at dealing with these byproducts. The end result is a less acidic muscle, one that has a new, higher threshold.

What Is Tempo Work and How Do I Determine Tempo Pace?

Tempo pace is not a single pace, but rather a range of paces both faster and slower than a calculated target. There are anaerobic threshold runs and aerobic threshold runs, both very effective. In our summer running program we use both, each done once per week. Tempo runs can be single bouts, such as 20-50 minutes at a specified tempo, or they can be run in two or more segments or bouts. (Some marathon runners do tempo runs in excess of 60 minutes). For instance, 20 minutes of tempo running can be divided into two segments of 10 minutes at tempo pace with 1-2 minutes easy jogging between segments.

The most important thing is to have an accurate idea of what your tempo pace range should be. Determining this is easier than you think. First, you find your vVo2, and then you do a little math.

There are many ways to determine vVo2, but the simplest method is to run a 1-mile time trial. Your pace for this effort is your vVo2. Then do the math. Your threshold training pace is 85-87% of your speed for the mile, and your aerobic threshold pace is 75-80%. It's important to note when calculating these ranges that it represents a percent of velocity, not percent of your mile time. For example, if you run the mile in 6:30, your threshold pace would be 6.5 minutes divided by 0.85-0.87, or 7:28-7:39 pace. Your aerobic threshold pace would be 8:07-8:40 pace.

Another method is to run a 6-minute time trial on a track. Then determine your vVo2 by using the following formula:

vVo2 = distance covered in meters/360.

For example, if you covered 1,500 meters in 6 minutes, your vVo2 would be 1,500/360 = 4.16 meters/second. To convert your meters/second to 400 pace, divide 400 by meters/second. In this example, 400/4.16 = 96 seconds. 96 seconds x 4 will give you a vVo2 mile time of 6:24. 85-87% of 6:24 is 7:21-7:31, which would be your threshold pace, and 75-80% is 8:00-8:32, which would be your aerobic threshold pace. You can also use a recent 5K to estimate vVo2. Simply subtract 20 seconds per mile from your 5K race pace to get a good approximation of your vVo2 velocity.

Tempo runs can also be done using heart rate as a guide. After determining your maximum heart rate (MHR), tempo runs can be done at 80-90% of MHR, with aerobic threshold runs at the lower end (80-85%) and anaerobic threshold runs at the upper end (85-90%).

Now to the fun part, designing a week's training using your vVo2.

Devote a day to each threshold (anaerobic and aerobic) and keep enough easy days in between so you're well rested. A general guideline is to start threshold runs with a 20-minute run. The best way to design any week of training is to start with the end in mind. What I mean by end is the weekend long run. (Long runs and recovery run pace can also be calculated by using 70-75% of your vVo2 pace.)

If you run your long run on Saturday, do your first tempo run on Tuesday. This gives you 2 days of easy running in between. Tuesday would be your threshold run day. Again, the 20-minute run doesn't need to be run in a single bout. 4x5 minutes with 1 minute's easy running, 2x10 minutes with 2 minute's easy jogging. Wednesday would be a recovery run, and Thursday would be your aerobic threshold run. Since the pace of the aerobic threshold run is slower, this run can be longer in duration. The same rule applies in dividing it up into manageable segments.

As a coach, the hardest concepts to communicate are the ideas of progression and overload. When do I add minutes to the tempo runs? How do I decide when to do the threshold paces? Tempo runs can be done all year long. Be patient and allow your body time to adapt. The only way to answer the second question is to perform a new vVo2 test or mile time trial periodically--say, every couple of months.

Remember: always design your training with your goal in mind. If you're focusing on a specific race--5K, 10K or marathon--decide where you want to be with your tempo runs in the weeks leading up to that event. Don't try to do too much too soon. Training is like combining two paints to make a new color. Once you add too much of one paint, you have to start over. Developing a higher form of fitness comes as a result of training systematically at various paces both faster and slower than your target pace. Stress both aerobic threshold and anaerobic threshold and you'll see the results.

Coach Michael Arenberg has an MBS in exercise physiology from the University of Colorado. He has been a competitive distance runner and triathlete for 37 years, completing 25 marathons and 11 Ironman triathlons, including 3 times qualifying for the Ironman World Championships. He has coached U.S. men's and women's Olympic Trial qualifiers in the marathon and two top-10 finishers in the U.S. Men's Marathon Championships, as well as multiple Ironman World Championship qualifiers. Coach Arenberg is available for coaching and can be contacted at makona94@aol.com If you have a training question for Coach Mike, send him an e-mail at makona94@aol.com. While he is unable to personally respond to every question, answers will appear from time to time in upcoming issues of Missouri Runner & Triathlete